From bfdb4458909946966e97a033d19d203c665c124f Mon Sep 17 00:00:00 2001
From: Arvid Norberg <arvid@libtorrent.org>
Date: Sun, 23 Feb 2014 19:13:53 +0000
Subject: [PATCH] merged SetFileValidData fix from RC_0_16

---
 ChangeLog                   |  1 +
 include/libtorrent/file.hpp |  2 ++
 src/file.cpp                | 10 ++++++++--
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 7f5c5feda..28436214e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -41,6 +41,7 @@
 	* fix uTP edge case where udp socket buffer fills up
 	* fix nagle implementation in uTP
 
+	* SetFileValidData fix on windows (prevents zero-fill)
 	* fix minor lock_files issue on unix
 
 0.16.15 release
diff --git a/include/libtorrent/file.hpp b/include/libtorrent/file.hpp
index 52bcec1fe..ca7b97e56 100644
--- a/include/libtorrent/file.hpp
+++ b/include/libtorrent/file.hpp
@@ -322,6 +322,8 @@ namespace libtorrent
 #endif
 #if defined TORRENT_WINDOWS
 		mutable int m_cluster_size;
+
+		static bool has_manage_volume_privs;
 #endif
 	};
 
diff --git a/src/file.cpp b/src/file.cpp
index f9e5d442c..5eed85350 100644
--- a/src/file.cpp
+++ b/src/file.cpp
@@ -946,6 +946,14 @@ namespace libtorrent
 	};
 #endif // TORRENT_WINDOWS
 
+
+#ifdef TORRENT_WINDOWS
+	bool get_manage_volume_privs();
+
+	// this needs to be run before CreateFile
+	bool file::has_manage_volume_privs = get_manage_volume_privs();
+#endif
+
 	file::file()
 #ifdef TORRENT_WINDOWS
 		: m_file_handle(INVALID_HANDLE_VALUE)
@@ -2025,8 +2033,6 @@ typedef struct _FILE_ALLOCATED_RANGE_BUFFER {
 
 	void set_file_valid_data(HANDLE f, boost::int64_t size)
 	{
-		static bool has_privs = get_manage_volume_privs();
-
 		typedef BOOL (WINAPI *SetFileValidData_t)(HANDLE, LONGLONG);
 		static SetFileValidData_t pSetFileValidData = NULL;
 		static bool failed_kernel32 = false;